diff --git a/plugin/client_test.go b/plugin/client_test.go
index fc28789c..03ddab0f 100644
--- a/plugin/client_test.go
+++ b/plugin/client_test.go
@@ -7,7 +7,6 @@
 package plugin
 
 import (
-	"bufio"
 	"io"
 	"os"
 	"path/filepath"
@@ -22,61 +21,40 @@ func TestMain(m *testing.M) {
 	switch filepath.Base(os.Args[0]) {
 	// TODO: deduplicate from cmd/age TestMain.
 	case "age-plugin-test":
-		switch os.Args[1] {
-		case "--age-plugin=recipient-v1":
-			scanner := bufio.NewScanner(os.Stdin)
-			scanner.Scan() // add-recipient
-			scanner.Scan() // body
-			scanner.Scan() // grease
-			scanner.Scan() // body
-			scanner.Scan() // wrap-file-key
-			scanner.Scan() // body
-			fileKey := scanner.Text()
-			scanner.Scan() // extension-labels
-			scanner.Scan() // body
-			scanner.Scan() // done
-			scanner.Scan() // body
-			os.Stdout.WriteString("-> recipient-stanza 0 test\n")
-			os.Stdout.WriteString(fileKey + "\n")
-			scanner.Scan() // ok
-			scanner.Scan() // body
-			os.Stdout.WriteString("-> done\n\n")
-			os.Exit(0)
-		default:
-			panic(os.Args[1])
-		}
+		p, _ := New("test")
+		p.HandleRecipient(func(data []byte) (age.Recipient, error) {
+			return testRecipient{}, nil
+		})
+		p.Main()
 	case "age-plugin-testpqc":
-		switch os.Args[1] {
-		case "--age-plugin=recipient-v1":
-			scanner := bufio.NewScanner(os.Stdin)
-			scanner.Scan() // add-recipient
-			scanner.Scan() // body
-			scanner.Scan() // grease
-			scanner.Scan() // body
-			scanner.Scan() // wrap-file-key
-			scanner.Scan() // body
-			fileKey := scanner.Text()
-			scanner.Scan() // extension-labels
-			scanner.Scan() // body
-			scanner.Scan() // done
-			scanner.Scan() // body
-			os.Stdout.WriteString("-> recipient-stanza 0 test\n")
-			os.Stdout.WriteString(fileKey + "\n")
-			scanner.Scan() // ok
-			scanner.Scan() // body
-			os.Stdout.WriteString("-> labels postquantum\n\n")
-			scanner.Scan() // ok
-			scanner.Scan() // body
-			os.Stdout.WriteString("-> done\n\n")
-			os.Exit(0)
-		default:
-			panic(os.Args[1])
-		}
+		p, _ := New("testpqc")
+		p.HandleRecipient(func(data []byte) (age.Recipient, error) {
+			return testPQCRecipient{}, nil
+		})
+		p.Main()
 	default:
 		os.Exit(m.Run())
 	}
 }
 
+type testRecipient struct{}
+
+func (testRecipient) Wrap(fileKey []byte) ([]*age.Stanza, error) {
+	return []*age.Stanza{{Type: "test", Body: fileKey}}, nil
+}
+
+type testPQCRecipient struct{}
+
+var _ age.RecipientWithLabels = testPQCRecipient{}
+
+func (testPQCRecipient) Wrap(fileKey []byte) ([]*age.Stanza, error) {
+	return []*age.Stanza{{Type: "test", Body: fileKey}}, nil
+}
+
+func (testPQCRecipient) WrapWithLabels(fileKey []byte) ([]*age.Stanza, []string, error) {
+	return []*age.Stanza{{Type: "test", Body: fileKey}}, []string{"postquantum"}, nil
+}
+
 func TestLabels(t *testing.T) {
 	if runtime.GOOS == "windows" {
 		t.Skip("Windows support is TODO")